With the Revolutionary War between the United States and Great Britain raging and American David Bushnell designed a weapon to counteract the the naval superiority of the British. His invention a submersible craft – the first submarine, to attack British ships in harbor. The craft, which became known as the Turtle, was large enough to hold one person. It had a ballast tank, which was filled to submerge the craft and emptied to give it buoyancy to rise.

Bushnell’s weapon for the Turtle was a charge that could be attached to a British ship and then explode. Bushnell called his weapon a torpedo, but it was in fact the first underwater mine. On September 7, 1776 the Turtle was sent to attack the British flagship the HMS Eagle in New York Harbor. The sailor at controls Sergeant Ezra Lee maneuvered the submarine next to the Eagle’s hull, but he failed to attach the mine to the hull.

The submarine eventually was lost when the British sank the ship transporting.